Changes in season, rulership, and human fortune are the stuff of which myth is made. Why should these themes pervade the mythologies of so many cultures? Might they even provide an explanation for seemingly unrelated myths and rituals? What these myths have in common, observes Thomas Worthen, is an ancient awareness that the heavens were subject to irregularities. The movement of stars we now attribute to precession was once a cause for concern about the stability of the world. Worthen here proposes the paradigm of "replacement" to account for the recurrence of common elements in the myths of many peoples. First citing the importance of rotation ritual in cultures as diverse as Buddhist and Gaelic, he draws on Georges Dum�zil's work with the Indo-European Ambrosia Cycle to lay the foundation for his paradigm. He then applies it to South American myths previously explored by Claude L�vi-Strauss, to the Greek myth of Phaethon, and to myths of dynastic replacement about Zeus and his forebears. He further shows show how the replacement paradigm explains a number of semantic puzzles in Indo-European studies, such as the relationship of words for "hammer" and "mill." The Myth of Replacement grandly illustrates the common knowledge of nature held by ancient peoples of the world. It offers scholars new perspectives on previously unconnected material as it provides general readers with a better understanding of the universality of myth.